西安市地下管廊混凝土耐久性能研究

Study on durability of concrete for underground pipe gallery in Xi’an city

针对地下管廊混凝土的特点,研究了膨胀剂、水泥基渗透结晶型防水材料、尾矿以及微珠对混凝土耐久性的影响。结果表明,微珠能大幅降低混凝土的干缩和抗裂试验中的裂缝面积;氯离子渗透性都属于极低范围,其中掺入水泥基渗透结晶型防水材料以及微珠的试件抗氯离子渗透性能最佳;抗水渗透试验结果与抗氯离子试验结果相似;不同的影响因素都能在一定程度上降低耐蚀系数,提升混凝土抗硫酸盐侵蚀的能力。

In view of the characteristics of concrete in underground pipe gallery,the effects of expansion agent,cement-based permeable crystalline material,tailings and microbeads on the durability of pipe-hanger concrete were studied. Tests have shown that the microspheres can significantly reduce the crack area in the concrete shrinkage and crack resistance test. The chloride ion permeability of this test is extremely low,and the test pieces doped with ruthenium and microbeads have the best resistance to chloride ion permeation. The test results of water penetration resistance are similar to those of the chloride ion resistance test. Dif-ferent influencing factors can reduce the corrosion resistance to a certain extent and improve the ability of concrete to resist sulfate attack.